tinysa ULTRA+ expert config

[phenol]

Has anyone gotten into the EXPERT CONFIG > INTERNALS menu yet? Looks like older models have mixer drive level options available there, but in ultra+ the menu is locked with a password.

[cte]

try 5432

[phenol]

thanks, it works

[DaneLaw]

A glance at some of the settings. (thx cte)

[phenol]

oddly enough,  nothing is selected in the mixer drive menu. 0-3dbm seems low for a level 13 mixer (ade-25mh)

[cte]

By reading the source code... I think the value set in the mixer drive menu (0...3) is written to DB3/DB4 of register 4 of an Analog Devices ADF4351 chip. Seems like the labels in the menu are not correct. Datasheet shows -4dBm / -1dBm / +2dBm / +5dBm. (it's not my source code, so I might be totally wrong)

• https://github.com/erikkaashoek/tinySA/blob/aa78ccc1cd9117840f09b7ac7ea3ceeb5d47ca53/ui.c#L2573
• https://github.com/erikkaashoek/tinySA/blob/aa78ccc1cd9117840f09b7ac7ea3ceeb5d47ca53/sa_core.c#L4499
• https://github.com/erikkaashoek/tinySA/blob/aa78ccc1cd9117840f09b7ac7ea3ceeb5d47ca53/si4468.c#L428

[phenol]

I think the ultra+ model has a different synthesizer, a Maxim part. the Imsai guy did a teardown on YouTube

[Jeroen3]

@cte There is a password on the expert menu so you RTFM before using these features because there are serious caveats.

[hugen]

Do not attempt to modify the mixer drive level of the ultra+. The ultra+ uses a higher gain and flatter LO amplifier than the ULTRA for higher frequency mixer drive, increasing the mixer drive level may saturate the LO amplifier producing a large amount of spurious signals.
Use the default AUTO option to ensure that the LO amplifier operates in the linear range and that the LO signal amplitude into the mixer is stabilized in the effective range of +10dBm to +14dBm.